(1) Field of the Invention
This invention relates generally to the field of Power Management Controllers and relates more specifically to script engines to replace hard-wired sequencers and control interfaces for power management integrated circuits (ICs) or other power management circuits.
(2) Description of the Prior Art
A Power Management IC (PMIC) is often used to control a number of supplies within an end device. The PMIC must switch these supplies on and off in a set order for the application to work correctly. A PMIC to support e.g. two known applications requires control logic to support both applications and often the requirements of both applications conflict. The only current solution is to add yet more configuration registers to select between features.
In regard of an open market product (application specific standard products—ASSP) as e.g. an PMIC, details of the signals or their timings are not known, which means very complex programmable interfaces are required to ensure that the PMIC is sufficiently flexible.
This causes the control logic extremely complicated to design. Often these added features result in undesired behavior in some modes, which requires exhaustive user-case testing, and there is no guarantee that all the end users requirements are met.
Different applications, and even powering up and down in some cases, can have conflicting requirements. With a traditional hard-wired approach these conflicts are difficult to identify before mounting on a board, and difficult to fix.
In order to support multiple applications with a single circuit a flexible approach consuming minimal power and being capable to be easily adapted should be achieved.
Using a microprocessor for this purpose would provide a flexible solution. The drawbacks of using a microprocessor are relative high power consumption, the amount of chip space required, and the requirement of a Software Development Kit for the processor.
Therefore other solutions are desirable combining high flexibility, low power consumption, and minimal chip size required.
Solutions dealing with power management controllers supporting multiple applications are described in following patents:
U.S. patent (U.S. Pat. No. 7,227,847 to Gluck) discloses an application based power management system comprising a power management application executed on a first device, wherein the power management application monitors communications interfaces for a plurality of applications in communication with one or more devices in a wireless environment, such that the power management application determines bandwidth and latency characteristics for each of the plurality of applications, and determines respective power management settings for each of the corresponding plurality of applications, wherein each respective power management setting optimizes data communicated by each of the applications in accordance with the corresponding bandwidth and latency characteristics.
U.S. patent application (U.S. Pat. No. 7,643,800 to Rofougaran) proposes a voice data and RF integrated circuit (IC) including a memory module that stores a least one application as a plurality of operational instructions, the at least one application having a plurality of power modes that each correspond to one of a plurality of use characteristics. A processing module executes the plurality of operational instructions, determines a selected one of the plurality of power modes based on current use characteristics of the at least one application, and generates a power mode signal based on the selected one of the plurality of power modes. An on-chip power management circuit receives the power mode signal and generates a plurality of power supply signals based on the power mode signal.
U.S. Patent Publication (US 2010/0145643 to Katpelly et al.) discloses a user-controlled application-based power management function provided for a battery-operated device. In general, for each of a number of applications of the battery-operated device, a power management function enables a user of the battery-operated device to provide a usage parameter for the application defining a desired amount of usage of the application for each of one or more tasks. For each task, the power management function determines an estimated amount of battery life that is sufficient to provide the desired amount of usage of the application for the task and determines whether the estimated amount of battery life is available. If the estimated amount of battery life is available, the power management function allocates an amount of battery life corresponding to the estimated amount of battery life to the application for the task.